Great post heavens I hadn't noticed that. It's a truely great addition that Gal Civ2 has needed since the beginning. Showing the tech cost and how many more research points needed to obtain that tech would be the cherry on top.
I got it to fire (you have to build all 5 modules, then assign the terror star a target, best to build the thing in your own territory and protect it with a good fleet because you can't even put any defense or attack modules on it!), but the game crashed after the animation played. Seems to turn the planets in the system into asteroid fields, but the models of them are all screwed up, that could be the cause *shrugs.